1. Technical Field
The present invention relates to a liquid ejecting head unit and a liquid ejecting apparatus, and more particularly, to an ink jet recording head and an ink jet recording apparatus ejecting ink as liquid.
2. Related Art
Liquid ejecting apparatuses represented by ink jet recording apparatuses such as ink jet printers and plotters include liquid ejecting head units (hereinafter, also referred to as head units) in which a plurality of liquid ejecting heads capable of ejecting liquid such as ink stored in an cartridge, a tank, or the like as liquid droplets is disposed.
The plurality of liquid ejecting heads is placed in a base plate that is a common holding member. The arrangement of the plurality of liquid ejecting heads is made such that nozzle rows, in which nozzle openings of each liquid ejecting head are arranged in parallel, are placed to be consecutive in the direction of the arrangement.
In order to improve the accuracy of the landing position of the liquid, each liquid ejecting head needs to be installed to the base plate after the position of the nozzle opening is determined with high accuracy. As a method of determining the position of the liquid ejecting head, for example, there is technology for forming key grooves and keys in an alignment substrate (corresponding to a base plate), which is formed from silicon, and components (corresponding to liquid ejecting heads) disposed thereon by using a photolithographic method and determining the positions of the components on the alignment substrate to be predetermined positions by fitting the keys into the key grooves (for example, see Japanese Patent No. 2549762).
However, in the above-described technology disclosed in Japanese Patent No. 2549762, silicon can be cracked easily. Thus, when the liquid ejecting head is repeatedly attached to and detached from the base plate, the keys or the key grooves for position determination are cracked or broken. Accordingly, the accuracy of the position of the liquid ejecting head with respect to the base plate decreases. Therefore, there is a problem that the accuracy of the landing position of the liquid is degraded.
In addition, such a problem is not limited to an ink jet recording head unit and exists also in a liquid ejecting head unit that ejects liquid other than ink.